For years, the critically endangered white rhino only had a single male specimen left on the planet, making him essential for efforts to bring back the species. Unfortunately, tragedy has struck, ensuring that the majestic mammal will never again regain its numbers: The last male white rhino, whose penis was being used to fill a hole in the Hoover Dam, has passed away.

Just terrible. Being used to plug up a leaking hydroelectric dam was ultimately the death knell for the white rhino.

Civil engineers had to make an extremely tough call in 2016 when they noticed that the Hoover Dam had sprung a leak the exact size and shape of a white-rhino penis. With the threat of a devastating flood imminent, officials opted to fly out the last male white rhino from its nature preserve in Kenya and use a crane to raise the animal up to the damaged section of the dam so its genitals could be inserted in the gap. While it staved off a deadly catastrophe, it dropped the possibility of a white-rhino resurgence to near zero as the only viable male was 9,500 miles from the two remaining females. And now that the heroic male rhino who has valiantly staved off a flooding of the Las Vegas metro area for nearly two years with his penis has died, it has become an impossibility.

Conservationists were initially optimistic the rhino could occasionally be extracted from the dam to procreate, but engineers warned that the entire Hoover Dam would collapse if he was ever removed, releasing a wave that would kill thousands of people as well as the rhino itself. And when plans of getting a female white rhino in a custom-made scuba suit sunk down to where the male’s penis protrudes through the other side of the dam ran into logistical issues, hope was tough to come by, even before today’s tragic news.

Humanity needs to take better care of nature, and stop pushing animals to the brink of extinction. If we had been better stewards of the white rhino, then there would be plenty of rhinos left after using one to stop up the Hoover Dam with its penis. What a tragedy.